What is Agile Development?

What is Agile Development?
Once primarily the domain of early adopters, Agile flavoured methodologies have
steadily gained acceptance as a mainstream approach to software development.1,2,3
Although Agile has come to mean many different things to different people, at its core,
it is a philosophy that guides a set of technically rigorous development practices. It
has been adopted by a growing number of organizations to lower the risk that is
inherent in software development and to deliver better software as defined by the end
user. As more teams adopt Agile practices and more companies transform to Agile
cultures, we continue to learn together about the best practices and benefits of
developing software in an Agile manner.
This introductory paper is designed to provide a basic understanding of Agile software
development.
© 2013 Intelliware Development Inc.

© 2013 Intelliware Development Inc. 3
The Foundations of Agile
A quick lesson in software development history provides context for both how
and why Agile is important. Agile is typically seen as an evolutionary step
forward from the “Waterfall” method, which is the traditional – and still most
prevalent – way of developing software.
Top 10 Agile Links
1. agilemanifesto.org
2. en.wikipedia.org/wiki/Agile_software_development
3. agilealliance.org
4. codeproject.com/Articles/604417/Agile-software-
development-methodologies-and-how-t
5. objectmentor.com/omSolutions/agile_what.html
6. agilemethodology.org/
7. mountaingoatsoftware.com/agile/new-to-agile-or-
scrum
8. allaboutagile.com/what-is-agile-10-key-principles/
9. versionone.com/Agile101/Agile-Development-
Overview/
10. i-proving.com

The Waterfall Method
Waterfall is a sequential approach to software development. As Figure
1 illustrates, it is a multi-step process with phases executed in a
stepwise manner. First, software requirements are defined. This is
followed by software design, then development and finally, integration
and testing. Often steps are defined by gates, at which point some
sort of approval, often involving a document, is required before the
project can proceed to the next step. Hence, the approach is also
often referred to as, “document driven development”.
Waterfall has obvious appeal. It provides an easily understandable
process that seems to progress in a logical sequence. Moreover, it’s a
familiar process because it is similar to how we build other things,
such as buildings and cars. The gates provide a form of risk
management, in that the process cannot proceed to the next step
without an authorization of the preceding step.
Figure 1: The Waterfall Process of Software Development

The Problem With Waterfall
The Waterfall approach works well if everything is straightforward, simple and
predictable. But therein lies the problem: software development is rarely
straightforward, simple and predictable. Waterfall poses the following risks:
1. Startup risk: Many projects fail to get off the ground because of the “analysis
paralysis” that is symptomatic of the Big Design Up Front (BDUF) approach. Projects
get stuck at a gate while various stakeholders hesitate to commit to a sign off.
2. Integration risk: The sequential approach of Waterfall development leaves
integration until near the end of development. Consequently, there is significant risk
that the software will have greater integration issues since it will be done all at once.
3. Cost risk: The cost of change in Waterfall projects is relatively high (see Figure
2) because it tries to minimize change by using BDUF (Big Design Up Front).
Figure 2: The Cost of Change: Traditional (Waterfall) vs. Agile4
The Cost of Change
Waterfall
Agile

The Problem With Waterfall (continued)
4. Delivery risk: Waterfall has a relatively high risk of failing to meet
deadlines or accommodate customer needs. Business needs inevitably
change throughout the development process (which can range from a few
months to years) and the Waterfall approach, by nature, does not take this
into account. Also, in a document driven development environment, a
development team may place more focus on delivering documentation
than on customer features.
5. Technical risk: Waterfall lacks rigorous practices of more modern
methodologies. These practices include unit testing, collaborative code-
base and frequent builds, all of which help ensure technical excellence.
To understand how these risks are avoided in modern approaches, it is
helpful to review a few key historical milestones in software development
methodologies.

From Waterfall to Agile
The Waterfall method has been prevalent in software development since the mid ’50s. It wasn’t until the late
‘60s and early ‘70s that references to iterative software development were made.5 In 1970, Winston W.
Royce was credited as one of the first people to describe the Waterfall approach and also be one of the first
to highlight its flaws, arguing for an iterative, Agile-like approach to software development. 6
In the mid ‘80s, after decades of experience with software developed using the Waterfall methodology,
change was needed. Software projects were earning the reputation of often being over budget, behind
schedule, and failing to meet the needs of end users. Overly complex software was the norm (Figure 3 pokes
fun at how this tends to happen when using BDUF). Then, in 1986, Frederick P. Brooks stated the following in
his landmark paper, “No Silver Bullet-Essence and Accident in Software Engineering”:
…it is really impossible for clients, even those working with software engineers, to specify completely,
precisely, and correctly the exact working requirements of a modern software product before having
built and tried some versions of the product they are specifying.
Therefore one of the most promising of the current technological efforts…is the development of
approaches and tools for rapid prototyping of systems as part of the iterative specification of
requirements.7 – Frederick P. Brooks
Over the next fifteen years, several “lightweight methodologies” were developed. In 2001, a group of software
leaders, in a field known at the time as lightweight methods, met to bring these new methodologies together
to find a better way to build software. The result was the Agile Manifesto.
Figure 3: The problem with guessing customer requirements

The Basics of Agile
Agile software development is comprised of
Values, Principles and Methodologies. The 4 Agile
Values serve as the foundation of Agile philosophy.
The 12 Agile Principles embody the Values and
provide more concrete examples of what Agile
means at a lower level. They form the Agile
philosophy that guides Agile Methodologies.

Agile Values
Agile is a somewhat loose term. If it had a motto, it would be embrace change.8 The Agile
Manifesto is accepted as the official definition of Agile and expresses the four foundational
Values of the philosophy:
Manifesto for Agile Software Development9
We are uncovering better ways of developing software by doing it and helping others do it.
Through this work we have come to value:
• Individuals and interactions over processes and tools
• Working software over comprehensive documentation
• Customer collaboration over contract negotiation
• Responding to change over following a plan
That is, while there is value in the items on the right, we value the items on the left more.
Kent Beck, Mike Beedle, Arie van Bennekum, Alistair Cockburn, Ward Cunningham, Martin Fowler, James Grenning, Jim Highsmith,
Andrew Hunt, Ron Jeffries, Jon Kern, Brian Marick, Robert C. Martin, Steve Mellor, Ken Schwaber, Jeff Sutherland, and Dave
Thomas.
© 2001, the above authors this declaration may be freely copied in any form, but only in its entirety through this notice.

Agile Principles
The 4 main Values of the Agile Manifesto guide the twelve Principles of Agile development,
which can be summarized as follows:
1. Satisfy the customer through early and continuous delivery of valuable software.
2. Welcome changing requirements, even late in development.
3. Deliver working software frequently.
4. Bring business people and developers together to work throughout the project.
5. Build projects around motivated individuals.
6. Communicate face-to-face when possible.
7. Measure progress primarily through working software.
8. Develop at a sustainable pace.
9. Focus on technical excellence and good design.
10. Simplicity, maximizing the amount of work not done, is essential.
11. Enable teams to self-organize.
12. Reflect at regular intervals on how the team can become more effective.

Agile Methodologies
Agile software development is perhaps best understood as a philosophy that guides several groups of
practices known as Methodologies. These Methodologies, which are like recipes to follow to help you
be Agile, include Scrum, Kanban, XP / Extreme Programming, Lean Programming and Agile
Modeling.10 Collectively, they comprise only a selection of the “lightweight methodologies” that can
be used to be Agile. While each Methodology has its nuances, the important thing to understand is
there is more than one way to practice Agile development.
While ground-breaking at the time, the Agile Manifesto has led to misconceptions about Agile as a
method-less, process-less approach. These claims are false. Many are based upon straw man
fallacies – oversimplifications of arguments to make the Agile Manifesto easier to attack. People
claim that “Agile has no documentation”. It’s a fallacious argument. Agile has documentation but
places a greater value on working software. As Agile co-creator Jim Highsmith said:
“The Agile movement is not anti-methodology, in fact, many of us want to restore credibility to
the word methodology. We want to restore a balance. We embrace modeling, but not in order
to file some diagram in a dusty corporate repository. We embrace documentation, but not
hundreds of pages of never-maintained and rarely-used tomes. We plan, but recognize the
limits of planning in a turbulent environment.”11 - Jim Highsmith, for the Agile Alliance
In addition to the Values, Principles and Methodologies, there are additional characteristics that are
common to organizations that have adopted Agile philosophies.

Agile Process
The Agile process takes a large software project and divides it into
many smaller pieces to be developed incrementally and iteratively.
Studies have found that project size and success are negatively
correlated, i.e. the shorter the project the higher the rate of success.12
The Agile approach helps reduce project size by effectively making
several mini-projects. It is the iterative approach that distinguishes Agile
from other methods.
Unlike traditional approaches, Agile has multiple planning and
development phases, known as iterations. Each iteration tends to be a
week or so of work. The development team and the customer team
work together to prioritize what will be included in each iteration. The
end result of the relatively short sprint is working software delivered to a
production-like environment where it can be tested by the customer.
This iterative process is repeated until the software project is
completed. Along the way, depending on the customer’s needs, there
can be a series of releases – software released to the end-user.

Agile Practices
There are dozens of Agile practices. Not all are used by Agile practitioners,
but those looking to be Agile should be aware of these key practices. Here
are some examples to help illustrate how the Agile values have been
applied into more concrete practices.
Daily Standup (Stand-Up Meetings)
Also referred to as a Daily Scrum, Agile teams have daily meetings to
briefly share need-to-know information. These meetings are held to keep
the development team on the same page, not to provide a status update to
the project manager. Brevity is the key to these meetings. In Daily Scrum
meetings, participants answer three questions13 :
1. What did I do yesterday?
2. What will I do today?
3. What problems are preventing me from making progress?

Agile Practices
User Stories
A User Story is a short description of a function that an
end-user would want. There are three elements to a
User Story:
• a written description for planning (card),
• a conversation about the story to better
understand it (conversation), and,
• a series of tests to confirm the story
(confirmation).14
Figure 4 provides an example of a User Story card.
These are written from the perspective of the end-user
in language that is understandable to them. Stories
serve as a form of currency between customers and
developers that both parties understand.
Figure 4: An example of a User Story for a Financial Services System

Agile Practices
Automated Testing
With Agile, a key aspect is the implementation of automated tests. Formal
and thorough automated tests help ensure the delivery of working software
throughout development and eliminate defects at the source. Developers
write test code using any number of available frameworks (e.g., JUnit is the
go-to Java framework) at the same time as they develop the code. In this
manner they build a safety net for the working code that allows them to
make changes and have confidence that other features haven’t been
broken. It also greatly reduces the length of time between the origin and the
discovery of a bug.
Acceptance tests are functional tests for a User Story. In other words, they
are programmed checks to ensure that existing features continue to work
as defined as new features are added. Ideally, acceptance tests are defined
by the customer and coded by developers. Running acceptance tests help
prove to the customer that the Story is done. After acceptance tests are
created, they are run automatically and repeatedly so that the newly
developed code works.

Agile Practices
Automated Builds
A key principle for Agile methodologies is to have running software at all
times. In practice, the only way to do this is by ensuring that all software
development is regularly and automatically compiled, built, deployed and
tested. This is usually done many times a day and at least once every time
a developer “checks in” code as a main part of the development branch.
The advantages for automating builds are huge. They reduce troublesome
deployment and integration problems and they provide a reliable
environment for demonstrations and testing.

Agile Practices
Agile Planning: Release, Iteration and Task
In Agile development, planning is divided into three levels: release, iteration and task. At the start of the
project, the developers and the customer come together to discuss the major User Stories (features)
that are needed in the software. They focus on identifying must-have features and roughly prioritizing
and estimating them, which helps facilitate Release, Iteration, and Task planning.
Release planning: A customer-driven planning session. The developers and the customer decide on a
date for the first in a series of product releases. They decide what stories to incorporate in the release.
The Developers drive the effort estimates for the stories while the customer drives the selection of the
stories. Effort estimates take various forms depending on the preferences of the development and
customer teams.
Iteration planning: A joint effort between the customer and developers to do part of the release plan.
As in release planning, the customer defines and prioritizes the User Stories and the developers
estimate the effort it will take to develop them. Naturally, the timeline is shorter for an iteration than that
of a release. It is often a matter of weeks, not months, for an iteration.
Task planning: After planning the iteration, the development team breaks down the stories for the
iteration into a series of tasks. A list of the tasks is documented in the project room where it is highly
visible; Post-it® notes and whiteboards are common tools to help with task planning. Developers sign up
for tasks and assign estimates to them.

Agile Practices
Pair Programming
This practice has two developers working together on a programming task.
Typically, one person takes the role of entering the code (the driver) while
the other thinks about the next steps and how this code will fit into the
bigger picture (the navigator).
A common objection to pair programming is that it is wasteful to have two
people doing the work of one. While it may take more developer time to
program this way, the output often justifies it. As one study found, pairing
takes 15% more effort than one person working alone but produces results
more quickly and with 15% fewer defects.16 Results will vary on a case-to-
case basis, but when considering pair programming, ask whether a
reduction in defects is worth added effort and resources. Also, pairing is not
a full-time requirement. Teams often set their own working rules around
when it is advantageous to pair.

Agile Practices
Continuous Integration
This practice has the development team integrate their code to the
system several times per day. Before integrating completed code,
the developer runs a series of tests to make sure the code to be
integrated won’t break any existing functionality or tests in the
system. To do so, the developer runs all of the tests for the system
and makes any necessary fixes. The more frequently code is
integrated, the less time it takes to merge and find errors.

Agile Practices
Retrospectives
A retrospective is a meeting to look back over an iteration, release, or
project, specifically to discuss what worked well, what could be improved,
and most importantly, how to translate the lessons learned into actionable
change. They are a forum for the team to improve upon their process.

The Business Benefits of Agile
Industry View
The appeal of an Agile approach to develop software incrementally and
iteratively continues to grow. Agile helps lower risks associated with
delivery, scope and budget that are common to every software
development project.
One MIT Sloan Management Review study on software
development practices found that early delivery of a partially
functioning system and frequent deliveries throughout
development are both positively correlated with higher quality
software.17 Agile enables the collaboration between the
development team and the customer, which offers the mutual
benefit of mitigating the inherently high risk of software
development.

Industry View
Version One’s 7th Annual State of Agile Development Survey found
that 90% of those who implemented Agile reported an improved ability
to manage changing priorities18. In addition, most (70%) believed that
Agile projects have a faster time to completion.19
Finally, in 2009, Dr. David F. Rico’s research and synthesis of
available data on Agile versus traditional methods20 identified many
compelling business benefits. In an analysis of 23 Agile versus 7,500
traditional projects21, Agile projects stacked up impressively well:
• 41% were better in terms of overall business value
• 83% achieved a faster time-to-market
• 50% were deemed to have higher quality
• 50% cost less
• 83% were seen as more productive

Our View
Intelliware has been involved with Agile since the very early days of Kent
Beck’s articulation of his Extreme Programming principles in the late
1990’s, at a time pre-dating the Agile Manifesto. For us, Beck and the rest
of the Agile pioneers articulated and validated many of the frustrations and
challenges we had experienced using Waterfall and BDUF. XP, and by
extension, Agile, offered an alternative that made sense and put simply,
worked.
Over the years, different projects have enjoyed a range of benefits as a
result of the application of Agile philosophies. However, there are four key
business benefits that our clients view as particularly important.

Our View
1. Get unstuck.
In all organizations, it is often very difficult to just get started. With
Waterfall, there are unreasonable demands to “nail the requirements”,
which fuels analysis paralysis. With Agile, a project can get started with
high-level requirements and a simple gating of the first level of useful
functionality. You need to have a high level map of where you are headed,
but the nitty-gritty detail work of fine-grained requirements, design, coding
and testing can be done more efficiently and with a higher degree of
quality when they are done in parallel.
Agile helps you get going. If you don’t start, you won’t get to the business
benefits of your project until it’s too late.

Our View
2. Change is built into the process.
The biggest fallacy of Waterfall is that you can “nail the requirements”. All
projects have change, and the longer they run, the more changes your
project will require. If all your software project plans are tied up in an
elaborate Microsoft Project®-style plan with dependencies, you and your
organization are in for a rough ride.
Agile software development builds change into the process from the get-go.

Our View
3. Risk is managed, your project is delivered.
Because change is built right into the process, and Agile depends on robust
technical practices such as automated testing and automated builds, you
have a running production system as early as day one. As the system grows,
and the project endures changes in requirements and design, the core
application is kept running. The risks associated with change are dealt with
daily, and so, at the end of the project, there isn’t a big bang release with a
mountain of hidden problems.
When steered properly, and with discipline, Agile projects get delivered.

Our View
4. Deliverable quality is higher.
Key drivers for better application quality include a number of the rigorous
Agile technical practices such as automated tests and builds. But another,
less talked about contributing factor to overall project quality is the effect
Agile processes have on the people involved with the project. Because of the
cross-functional nature of Agile teams, questions get answered quickly,
roadblocks can be removed, and the team is motivated to work together
towards a common end goal. It’s not a year-long project; it’s a series of one
or two week sprints with real deliverables in a short period of time. It’s a
satisfying and energizing manner in which to work.
Stronger technical practices and greater overall team motivation all combine
to result in higher quality project deliverables.

Is Agile right for you?
A transition to Agile is not a trivial effort, nor is it necessarily for everyone. A
common pitfall is to try a few Agile practices that seem convenient and ignore
those that seem difficult. This often results in a failed transition based on faulty
assumptions and missing pieces. A truly sustainable Agile transformation requires
a significant change in culture within your organization. Take time to really
appreciate what Agile entails, understand the main barriers to adoption and
consider its compatibility with your organization before starting implementation.

Sources
1 Scott M. Ambler and Matthew Holitza. Agile for Dummies. Hoboken: John Wiley & Sons, 2012. Print.
2 Krill, Paul. “Agile software development is now mainstream”. InfoWorld. The IDG Network. 22 Jan. 2010. Web.
3 Heusser, Matthew. “Has Agile Software Development Gone Mainstream?” CIO.com. CXO Media Inc. 12 Aug. 2013.
4 Ambler, Scott. “Examining the Agile Cost of Change Curve”. Scott W. Ambler + Associates. Ambysoft Inc. 2002. Web.
5 Larman, Craig and Basili, Victor R. “Iterative and Incremental Development: A Brief History”. C2.com. 21 Apr. 2011. Web.
6 Winston, Royce, W. “Managing the Development of Large Software Systems", Proceedings of IEEE WESCON 26 (1970). Web.
7 Brooks, Frederick P. “Silver Bullet: Essence and Accidents of Software Engineering”. Pgs. 13-14 Computer In Computer, Vol. 20, No. 4. (1987). Web.
8 Craig Larman. “Agile & Iterative Development: A Manager’s Guide”. Boston: Pearson Education. 2004. Print.
9 Beck, Kent et al. “Manifesto for Agile Software Development”. Agilemanifesto.org. 2001. Web. 15 Sept, 2013.
10 Scott M. Ambler and Matthew Holitza. Agile for Dummies. Hoboken: John Wiley & Sons, 2012. Print.
11 Highsmith, Jim. “History: The Agile Manifesto”. Agilemanifesto.org. 2001. Web.
12 Craig Larman. “Agile & Iterative Development: A Manager’s Guide”. Boston: Pearson Education. 2004. Print.
13 Shore, James, Warden, Shane. The Art of Agile Development. Sebastopol: O’Reilly Media, Inc., 2008. Print.
14 Mike Cohn. “User Stories Applied: For Agile Software Development”. Boston: Pearson. 2004. Print. Reference also to Ron Jeffries (2001)
15 Wake, Bill. “INVEST in Good Stories, and SMART Tasks”. XP123. Web.
16 Shore, James, Warden, Shane. The Art of Agile Development. Sebastopol: O’Reilly Media, Inc., 2008. Print.
17 MacCormack, Alan. “Product-Development Practices That Work: How Internet Companies Build Software”. MIT Sloan Management Review. 2001. Web.
18 VersionOne®, 7th Annual State of Agile Development Survey © 2013.
19 VersionOne®, 7th Annual State of Agile Development Survey © 2013.
20 Dr. David F. Rico, PMP, CSM, “Business Value of Agile Methods – Cost and Benefit Analysis” davidfrico.com/rico09e.pdf, 2009.
21 Mah, M. (2008). Measuring agile in the enterprise: Proceedings of the Agile 2008 Conference, Toronto, Canada.

What is Agile Development?

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